Compare towns by surface-water flood coverage
Explore the share of town land mapped at high or medium surface-water flood risk, grouped by coverage rather than ranked.
NaFRA2 RoFSW v202509 · 6,807 eligible towns
How to read this comparison
These figures measure town land area, not homes affected. Zero mapped high-or-medium coverage is not flood-free: lower-probability flooding is excluded, and the map cannot settle an individual property’s risk.
Eligibility, ordering and limitations
A complete, published controlled present-day RoFSW result for the town. Missing results are excluded, never treated as zero.
We add the High and Medium category areas intersecting each ONS built-up-area boundary. High means at least a 3.3% annual chance; Medium means at least 1% but below 3.3%. Their combined coverage therefore describes mapped land with at least a 1% annual chance. We use present-day mapping, not a future climate-change scenario.
The coverage groups are Kerbside presentation thresholds, not Environment Agency probability categories. Towns are alphabetical without ranks. We retain four-decimal precision for grouping and display a positive share below 0.01% as <0.01%, not zero. Missing controlled results are excluded.
Explore the coverage groups
6,807 matching towns from 6,807 eligible towns. Alphabetical listing; no ranks.
Scroll sideways to see all columns.
| Town | High / medium land area | Coverage band |
|---|---|---|
| Great DunmowEssex | 2.51% | 1% to below 5% |
| Great Easton (Harborough)Leicestershire | 7.77% | 5% or more |
| Great Easton (Uttlesford)Essex | 1.28% | 1% to below 5% |
| Great EcclestonLancashire | 3.71% | 1% to below 5% |
| Great EllinghamNorfolk | 3.07% | 1% to below 5% |
| Great EversdenCambridgeshire | 8.25% | 5% or more |
| Great FinboroughSuffolk | 1.06% | 1% to below 5% |
| Great GiddingCambridgeshire | 6.94% | 5% or more |
| Great GlenLeicestershire | 3.70% | 1% to below 5% |
| Great GonerbyLincolnshire | 7.59% | 5% or more |
| Great GransdenCambridgeshire | 4.21% | 1% to below 5% |
| Great GreenSuffolk | 4.00% | 1% to below 5% |
| Great HaleLincolnshire | 9.38% | 5% or more |
| Great HarwoodLancashire | 4.15% | 1% to below 5% |
| Great HaseleyOxfordshire | 6.44% | 5% or more |
| Great HaywoodStaffordshire | 6.03% | 5% or more |
| Great HockhamNorfolk | 2.01% | 1% to below 5% |
| Great HollandEssex | 6.17% | 5% or more |
| Great HorkesleyEssex | 1.20% | 1% to below 5% |
| Great HormeadHertfordshire | 3.39% | 1% to below 5% |
| Great HorwoodBuckinghamshire | 2.57% | 1% to below 5% |
| Great Houghton (Barnsley)Barnsley | 1.54% | 1% to below 5% |
| Great Houghton (West Northamptonshire)West Northamptonshire | 0.00% | 0% mapped high / medium |
| Great KimbleBuckinghamshire | 0.76% | Above 0%, below 1% |
| Great KingshillBuckinghamshire | 2.60% | 1% to below 5% |
Environment Agency · NaFRA2 RoFSW v202509. Source details
How is this different from Flood Zone 3?
Surface-water flooding happens when rainwater cannot drain away or soak into the ground. Flood Zone 3 is a separate river-and-sea planning measure. Neither town-wide land percentage tells you whether a particular home will flood; check the exact address.
Check long-term flood risk for an addressCheck both kinds of flood mapping
Planning flood zones and surface-water coverage answer different questions. Explore Flood Zone 3 coverage
Data sources
Dates below distinguish the period represented by the data from when the source was collected and published here. How we use these sources
Risk of Flooding from Surface WaterEnvironment Agency · NaFRA2 RoFSW v202509
- Data version
- NaFRA2 RoFSW v202509
- Source published
- 17 September 2025
- Retrieved by Kerbside
- 2 September 2026
- Published on Kerbside
- 2 September 2026
- Refresh cadence
- as needed
- Towns with a published result
- 6,807
Open original source · Open Government Licence v3.0
Publication reference: 5ebbae90-38ab-4f73-abc7-b515beec4ae8. A published result is not a guarantee of complete local coverage.